The present invention relates to an electronic apparatus having a built-in hard disk device that is provided with a thermistor sensor for detecting an internal temperature of the hard disk device, and when the internal temperature detected by the thermistor sensor at the time of recording information is higher than a predetermined temperature, the hard disk device executing a self-diagnosis function to read out the once recorded information again, thus verifying the contents of the recorded information. For example, the invention relates to an electronic apparatus such as a DVD recorder having a built-in hard disk device or a liquid crystal TV having a built-in hard disk device.
In the past, in various kinds of electronic apparatuses such as a DVD recorder or a liquid crystal TV, there has been employed a technique in which a temperature sensor is disposed inside the apparatus to monitor the internal temperature of the apparatus, and when the internal temperature of the apparatus abnormally rises, a cooling fan is driven, or the abnormality is notified to a user, for example, by displaying an error message, thereby preventing a possible malfunction of the apparatus (see Patent Documents 1 to 4, for example).
A recording device disclosed in Patent Document 1 is a DVD video recorder with a hard disk drive (HDD). The recording device is configured such that a temperature detecting section such as a thermistor sensor directly detects the internal temperature of the recording device and when the internal temperature of the recording device excessively rises, the internal temperature of the recording device is lowered by controlling a cooling fan.
An optical information recording and reproducing device disclosed in Patent Document 2 is configured such that a thermistor sensor directly measures the internal temperature of the device and when it is detected that the measured temperature is higher than a predetermined value, the detection result is outputted to the outside to caution.
An information processing system with a temperature detection function disclosed in Patent Document 3 is provided with temperature detection means for directly detecting the internal temperature of a file memory device to prevent destruction of the file memory content which may caused by an access to the file memory device when the internal temperature is high. In the information processing system, it is determined whether or not the temperature detected by the temperature detection means is higher than a predetermined temperature. When the temperature is detected to be higher than the predetermined temperature, an operation of protecting the stored content is executed.
A disk device disclosed in Patent document 4 is provided with temperature detection means for directly detecting a temperature of the disk device. In the disk device, it is determined whether or not the temperature detected by the temperature detection means is within a range of temperature that guarantees a secure operation of the disk device. When it is determined that the detected temperature is outside the guarantee range, the disk device invalidate a write cash function and an automatic substitute function. When receiving a write command, the disk device executes verification after performing a write to the disk so as to confirm whether or not the write can be normally executed.
Patent Document 1: Japanese Patent Publication No. 2002-324391A
Patent Document 2: Japanese Patent Publication No. 03-268291A
Patent Document 3: Japanese Patent Publication No. 06-67910A
Patent Document 4: Japanese Patent Publication No. 2003-297025A
According to Patent Documents 1 to 4, the temperature detection means is provided inside a device of which the internal temperature is to be monitored. The internal temperature of the device is directly detected by the temperature detection means, and on the basis of the detected temperature, the control of the cooling fan, the display of the message, the write to the disk, or the like are performed. However, the respective devices disclosed in Patent Documents 1 to 4 require the temperature detection means for directly detecting the internal temperature of the device.
Recently, electronic apparatuses having a built-in hard disk drive (HDD) have become widely used as a recording medium. The hard disk drive has a large recording capacity and a very fast access speed. In this respect, such electronic apparatuses having the built-in hard disk drive will become more widely used.
Since the hard disk drive is used as an auxiliary memory device of a computer, the hard disk drive requires high reliability in information recording and reproduction. For this reason, the hard disk drive is generally hermetically enclosed in a metallic case. Various methods have been devised for controlling internal operations of the hard disk drive. For example, there is a method in which a thermistor sensor is installed in the hard disk drive to detect the internal temperature, and when the internal temperature of the hard disk drive detected by the thermistor sensor at the time of recording information is lower than a predetermined lower limit temperature or is higher than a predetermined upper limit temperature, the hard disk drive executes a self-diagnosis function (hereinafter, referred to as “write verification”) to read out the once recorded information again, thus verifying the contents of the recorded information. In this case, the predetermined lower limit temperature is set to 20° C., for example. This is because if the information is recorded at a temperature lower than 20° C., the information may be improperly recorded. Meanwhile, the predetermined upper limit temperature is set to 60° C., for example. This is because if the information is recorded at a temperature higher than 60° C., the information may be improperly recorded.
As described above, the hard disk drive has the thermistor sensor inside the case as the temperature detection means for detecting the internal temperature, and the hard disk drive stores information about the temperature detected by the thermistor sensor.